The groups have increased the tempo of their attacks in recent months, and are showing signs of coordinating military efforts around the country. Government officials say the groups pose no immediate threat to the popularly elected president, beloved by much of Haiti’s poor majority. But the groups have added a potent new element to a civilian opposition movement that had failed to generate much interest beyond the capital, broadening its reach for the first time into provincial regions traditionally supportive of the president.

Opposition political leaders have declined to condemn the armed attacks, although they deny having political or financial connections to them. Instead, they blame Aristide for the deteriorating security situation, which has complicated government efforts to hold new elections that are a condition for the lifting of U.S. aid restrictions.

The uprising here in Gonaives, 70 miles north of Port-au-Prince, the capital, has centered in the seaside slum of Raboteau. About 30 armed men have sealed off the neighborhood since September to protest the killing of Amiot Metayer, the leader of a pro-Aristide community organization, whose body was found on a roadside south of here. His eyes were shot out.

Metayer’s followers say the armed group once regularly received money from Aristide’s Lavalas party, as well as dozens of guns to defend the president following a December 2001 coup attempt. They have since turned the arsenal against their former patrons, whom they accuse of killing Metayer.

"We want him to go," Butteur Metayer, the 32-year-old brother of the slain man, said as gunfire rang out last week between his men and the police. "He’s killed too many people," he said. "Goodbye, Aristide, forever."

The violence is deepening Haiti’s political crisis at a time when Aristide’s government, stunningly short of resources, is largely powerless to stem it. Aristide is a former Catholic priest whose defiance of the Duvalier family dictatorship helped force it from power in 1986. In 1990, he became the first freely elected leader in Haiti’s 200-year history, only to be deposed within seven months by a military junta.

A U.S. force of 23,000 troops restored Aristide’s government in 1994, part of a $2.3 billion attempt at nation-building. Roger Noriega, assistant secretary of state for Western Hemisphere Affairs, recently characterized the effort as "a complete failure due to the Haitian leader’s inability and lack of willingness to move the country along a democratic path."

Since his reelection in November 2000, Aristide has pushed with mixed success a populist agenda of higher minimum wages, school construction, literacy programs, higher taxes on the rich and other policies that have angered an opposition movement run largely by a mulatto elite that has traditionally controlled Haiti’s economy.

The United States has enforced a freeze on international loans totaling $500 million to Haiti over that time because of the government’s failure to address fraudulent legislative elections held before Aristide took office. Last year, the Bush administration agreed to unfreeze a $146 million Inter-American Development Bank loan for roads, water systems, education and public health programs. But after paying more than $30 million in back interest, Haiti is still waiting for the first disbursement.

Government officials say the effects of that policy have hampered their ability to address poverty, which afflicts 80 percent of Haiti’s 8 million people, or effectively deal with U.S. concerns over Haiti’s role as transshipment point for Colombian cocaine and illegal migration to the United States. Instead, they say, U.S. policies have empowered the opposition movement.

Before new elections, which could free up the rest of the money, can be held, the Organization of American States has called on Aristide to create an impartial elections board and improve security in a country where partisan gangs are part of a winner-take-all political culture. The 12-party opposition coalition known as the Democratic Convergence, created with the help of the U.S.-funded International Republican Institute that continues to advise the group through seminars in the Dominican Republic, has declined to participate in selecting the panel, citing security concerns.

Last week, a coalition of civic organizations known as the Group of 184, headed by a U.S.-born businessman named Andre Apaid Jr., organized a rally in Port-au-Prince. The event was ostensibly arranged to outline what the group refers to as its social contract, which calls on Aristide to turn over power to a "council of wise men" appointed by an impartial elections commission. But the rally ended in a haze of tear gas and rock-throwing clashes between groups of Lavalas supporters and the opposition. Waving open hands in a five-fingered salute representing Aristide’s five-year term, Lavalas members turned out in far larger numbers than the opposition. Apaid, whose brother-in-law and nephew were arrested for gun possession during the rally, said the event was "confirmation the government is lowering the mask of its dictatorship."

Yvon Neptune, Haiti’s prime minister, said the rally was part of a broader opposition strategy to create "a psychosis of insecurity" in the country and make municipal and parliamentary elections, scheduled for early next year, impossible to hold.

"Our information is that there are links between some elements of these armed groups with the opposition on every level -- financial as well as the political goal of ousting President Aristide," Neptune said. "We’re trying to show that this is all a pretext for not wanting to participate in elections."

The first armed group appeared last year along the Massacre River that defines Haiti’s border with the Dominican Republic. Members of the group now slip across the border for refuge. The leaders were 10 former Haitian army soldiers, none of higher rank than sergeant. The roughly 7,000 former members of the military have been a constant source of resistance since the army’s dissolution, increasingly so as the national police force created by the United States to replace it has shrunk from 5,000 to 3,500 members because of financial difficulties.

Armed groups, none larger than 50 people, have also emerged in Petit-Goave on the island’s southern finger, in the northern city of Cap-Haitien, and here in Gonaives, a city of 200,000 people where a chalky coastal plain meets a turquoise sea. The government’s one helicopter has been shot up and repaired repeatedly over the past year as the groups have stepped up attacks, including the killing of six members of an Interior Ministry delegation to the central plateau and the wounding of the police chief here.

"What they are trying to do is divide our forces," said Franz Gabriel, Aristide’s security adviser.

Neptune denies that Lavalas passed out weapons following the December 2001 attack on the National Palace, which Aristide characterized as a coup attempt. But Raboteau, the site of a 1994 massacre directed by the military that killed 15 people, is awash in guns. The men carrying them say the weapons came from Lavalas.

Burning tires, rusting car chassis, and piles of garbage block the roads into the slum. Passing police patrols draw and return fire along rows of flimsy houses made of tattered wood, cement blocks and sheets of tin. Conch shells, bleached by the sun, run along the tops of walls.

The young men manning the barricades claim to be part of a pro-democracy movement. But during a break in a gun fight with police, a handful of them broke down the door of a house owned by a man named William Joseph. They tossed chairs, tables, a chest of drawers, a television set into the street, then set the pile on fire. Joseph, they said, was an informant for Lavalas.

"I don’t know who the police are after," said Jacques, a 26-year-old unemployed mason afraid to give his last name. "But the police are only trying to do their job."

Metayer’s group was called the Cannibal Army. As its name suggests, it was not a benign force. Police officials say it exacted "taxes" from cars passing through the slum, and boats that docked at the port. It may have had a hand in drug trafficking, police say.

The group’s turn against Aristide began with Metayer’s arrest in July 2002 after he was implicated in the death of an opposition member. Until then Metayer had been the conduit for Lavalas patronage, the slum’s economic lifeblood, that made him a big man in a country where politics are dominated by personalities.

A month later, a group of his followers plowed a tractor through the wall of the Gonaives prison, freeing Metayer and 159 others. Among them was Jean Tatoune, a former leader of the anti-Duvalier movement who was serving a life sentence for his role in the Raboteau massacre. Police have issued a $17,000 reward for Tatoune’s arrest, but no one has delivered him so far.

"He’s a heavyweight in this," said Dieujuste Jeanty, who calls himself a leader in the Cannibal Army. "This is not just a movement sitting here in Gonaives."